Web-tensioning device.



'e. H. L EWIS, WEB TENSIONING DEVICE. APPLICATION 'HLED FEB- 2?,1913'.

Patented Feb. 12, 1918.

l 1 IN VEIY TOR. 54560225):

A TTORNE YS.

WITNESS UNITED strATEsrATENroFFIon.

GEORGE H. LQWIS, OI CHIGOPEE FALLS, MASSACHUSETTS, ABBIGIN'OB TO THE FIST RUBBER COMPANYQ QF CHIGOPEE FALLS,'MASSACHUBETTS,'A CORPORATION 03.x

MASSACHUSETTS.

wnn-rlinszonmo nnvio Bpccitlcaflon of Letters Patent.

Patented Feb. 12, 19181.

Application filed February 27, 1917. Serial No. 151,353.

To all whom it may concern:

Be it'known that I Groaon H. LEWIS, a

citizen of the United states of America, re-' siding at Chicopee Falls, in thccounty of Hampden and State of Massachusetts, have invented certainnew and useful Improvements in Web-Tensionin Devices, of which the following is a speci catioh.

This invention relates to improvements in web tensioning devices for calenders.

Devices of this character are desirable when the web is unwound from a roll and drawn through the machine by the pull of the calender rolls themselves. It is usual to provide a braking mechanism to retard the rotation of the unwinding roll, but ohviously, since the diameter of the latter con- ,tinu'ally diminishes, the tension ofthe web will increase unless the braking pressurebe diminished. Various mechanisms have been provided heretofore toautomatically vvary to the machine.

operated by unskilled labor. '1

v supply roll.

the unwinding roll.

.the braking pressure to keep thetension of constant as it-is unwound from the Such mechanisms, however, are necessarily elaborate and expensive, and cost of installing} and using these automatic devices is not justified. For example, such devices are generally not applicable to existing ma chines without an extensive reconstruction and, indeed, itmay even be necessary an entirely new machine to obtain the automatic mechanism for the latter is seldom sold as a separate article. Moreoverg'in the operation of calenders, there is always an operator whose function it is to supply. rolls These rolls are brought to this operator, and,"after one has been inserted in the machine, he has nothing as a rule to do uiitil a new roll is required. to have the operator Therefore, itis usual stand by to ad]ust the braking pressure on The variations in braking, pressure by this method are left eutirely to the 'udgmen't of the operator so that it is essentiai to have skilled operators in order to obtain satisfactory results. The difficulty arises, however, that experienced operators ar'e seldom obtained for this class of work, and it is necessary to provide a ten sioning devicewhi'ch may be satist'zurtorily his invention the web seeks to supply a simple means for indicat ing the tension to the operator, so that personal judgment on his part 4.5 not required,

to buy and the braking-pressure may be accurately varied to maintain the web under constant tension. i

The object of the invention isto provide a device for indicating automatically the tension of a web as it passes through the cal-- ender, the devicebeiug characterized in thatit involves a simple yet efiicient arrangement of mechanical structure which may be read i'ly applied as an attachment to any existing calender new or 01 a The invention in an embodiment at. pres ent preferred, is shown for illustrative pin poses in the accompanying drawings, in which- Figure l is a side elevational view of a calender showing the invention as applied thereto;

Fig. 2 is a rear elevational view of Fig. 1;

Figs. 3 and 4 are top plan views of the lower and upper braking. members, respectively; and Fi 5 is a'sectional elevation of the tension in icator.

Referring to these drawings, reference (1 .indicates the frame of a calender and b the web a of the material to be calendered is an wound from a roll '01 and passed through the rolls 6 in the manner shown in Fig. 1. Passing through rolld is a rod e1 which is square 1n cross sectional shape, and is adapted to turn with the roll. One end of roll e is adapted to fit in a square socket in a head f (Fig. 2) and at the other end is :1 cylindrical portion 6 which rests in a U-shaped bracket 9 fixed to frame a. Head 7 an integral part of a shaft It rotatably moh a bracket 1: fixed to frame a, as best shown in Fig. 2, and on the end of shaft h is fixed a flanged drum j upon which the braking pres sure is applied to retard the rotation of roll (I. The devices so far'described are of the usual characterand illustrate the customary way of removably mounting a stock roll in a calender. i A

The usual way to apply ressure to drum f is by a weighted brake and or the like, but, instead of employing the customary mechanism, other devices, now to be described, are used. Two brako'straps 7 and S are arranged to engage the upper and lower peripheral portions of drum j. Strap '8, as

shown in Figs. 1 and 3,2111 extended pc' mted in tion 9. which is formed by a quarter turn the operators function to keep the latter bend in the strap. Strap 7 is pivotally con-' stationary at a designated graduation on nected at 10' to the portion 9, and, as shown scale 16. However, as the roll (1 unwinds in Fig. 5, the looped end to receive pivot 10 and diminishes in diameter, it must rotate 5 is of less width than the remainder of the more rapidly, since the surface speed of the 70 strap to permit the extended portion 9' of web is constant, or the tension n tlie web .strap 8 to passthcreby. at. hand screw 11, 'will increase; Accordingly, the operator threaded into the. flanged end of strap 8, loosens the screw 11 to diminish the pressure fpasses loosely through the correspondingly on drum and makesadjustments of the.

10 flanged end of strap '7. and coiled around screwfrom time to'time as'oftenas is Mass 75 screw 11 is a sprin 12 which tends to sepa-" 'sary to keep the pointer 15. at ,the desired rate the flanged en 5. By turning screw 11, scale graduation. the straps 7 and 8 may be forced against the If desired, a brake band and indicating periphery of drum j in an obviot'ismanner. mechanism as described may be at one on Fixed to a hanger 13, extending outwardly each side of the calender. In t iis case, a- 8'0 and downwardly from the top of frame it, simple clutch device would be added to conis an indicator 14 which may consist simply nect the bar 0 and the second shaft h to be ofa spring balance or scales. The indicator placed at the left hand side of the calender, has-a pointer 15 'which is movable over. a as seen in Fig. 2. In all other respects, the

2 0 suitably graduated scale 16 when a'force 1s attachment at the left side of the machine 85 applied to a book 17. Any of the wellwould be the same as that already described. known mechanisms may be employed to The duplicate description and illustration actuate pointer '15 from hook "17. The is thought to be unnecessary and has, there-l mechanism showrff in Fig. 5 may be emfore, been omitted.

p10 ed, for example, and this mechanism It is to be noted iprticularly that the de- ,90 .wil be described merely a fs an illustrative vice described can e readily and convenexample of one operable means of accomiently applied to'an existin calender withplishmg the desired function. C-shaped out much expense. No mo ification of the spring 18 is suspended at 19 fro the top calender is required-except the substitution of and within the indicator casing and hookof the brake straps. It is only necessary to 17, passing loosely through the latter, is provide means to attach the. bracket 13 to attached to the lower end of the spring. the'machine and thereafter the few remain- Links 20 and 21 pivotally connected to the ,ing parts may be applied quickly and withupper and lower ends, respectively, of spring out difiicultv. Any standard spring scales 7 3b 1 are pivotally connected at dilierent points may be use and the other parts are simto an arm 22, and on the end ,of the latter is ple. The expense of'manufacturing the dea pin 23 which is movable in a slot 24 (Fig. vice is, therefore, small as is also the cost 2) in the face of indicator 14 and has its of installation for the reason that no change end resting in a slot 25 in the pointer 15. in the e'xistingstructure is required. 40 The'mechanism just described is well known The device described is, howevr, particu in the art as a sprin balance or dynamomelarly useful in the operationof calendars for ter. As weight is. laced upon thehook 17, it is most desirable that the tension of the the ends of the -s'haped spring 18 are web be kept substantially constant. Variadrawn apart, and the separation of these 'tions above or below the re uired tension ti ends is arranged to swing arm 23 and thus will work injury 'to the we By using the pointer 15. The hook 17 is connected by the structure described, the operator, even alink 25 to the end of the member 9. though he be unskilled, can tell when ad- The operation of the invention willnow justments are needed by watching the indibe described. The square rod (2 is slipped cator and can, therefore, get he desired 50 into the roll (1 of materialto be calendered. tension in the web 'aswell as to thereafter One end of the rod is then fitted into the maintain the tension substantially constant socket in head f, and the other end lowered during the calendering of the'entire web. into the opentop of the U-shaped bearing 9. a The invention has beendescribed in a pre- The end of the web a from roll d'istien ferred form for illustrative (purposes, but v 56 threaded throu h the calender in the usual the scope of the invention is efined by th'e12o manner after w ich the normal calendering appended claims rather than by the foregoo ration ensues. With the machine in moin description.

tion, the operator turns the screw 12 until hat I claim isthe pointer 15 comes to the desired position 1. A'web-tensioning device 11. 1? calenders it) on scale 1'5. The force acting to turn roll d, andfthe like, comprising in. combination an 4 5 ,whichis etipal to the tension in the web a, arbor to support the webin roll fornud posed ythe ring 23,'acting through friction drum rotatable bythe arbor as the levers and bra e band. andt e spring web is unwound fgojm the brake ban deflected until the forces are balanced members"hinged ttclgether .atpnefend and when pointer '15 becomes statior'n' It 18 adaptedtcrencirdle'the drum, adjustable' u means to draw the other ends of said membrake band members hinged together at one 15 bers together to apply pressure to the drum, end and adapted to encircle the drum, adan arm extending from one of the brake justable means to draw the other ends of bands, and means connected to said arm to said'members together to apply pressure to balance the tension in the web and indicate the drum, an arm extending from'one of the variations in web tension as a guide for adbrake bands, an indicating spring balance 20 justing the first-named means. fixed to the frame and a link connecting the 2. A Web tensioning device for calenders, balance to said arm, all constructed and arcomprising in combination with the calender ranged so that the tension of the web is frame, a shaft rotatably mounted on the latmeasured by the spring balance and so that ter, an arbor having a removable driving the indications of the latter may be used as 25 engagement with the shaft and having a rea guide to the adjustment of said means. movable rotatable engagement with a part of said frame, a brake drum on said shaft, GEORGE H. LEWIS. 

